added auto html to plain text mail generation

ayalamih · Aug 26, 2022 · 0f9ddbf · 0f9ddbf
1 parent f14105b
commit 0f9ddbf
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Showing 13 changed files with 255 additions and 14 deletions.
diff --git a/tools/mailer/html2text.go b/tools/mailer/html2text.go
@@ -0,0 +1,105 @@
+package mailer
+
+import (
+	"regexp"
+	"strings"
+
+	"github.com/pocketbase/pocketbase/tools/list"
+	"golang.org/x/net/html"
+)
+
+var whitespaceRegex = regexp.MustCompile(`\s+`)
+
+// Very rudimentary auto HTML to Text mail body converter.
+//
+// Caveats:
+// - This method doesn't check for correctness of the HTML document.
+// - Links will be converted to "[text](url)" format.
+// - List items (<li>) are prefixed with "- ".
+// - Indentation is stripped (both tabs and spaces).
+// - Trailing spaces are preserved.
+// - Multiple consequence newlines are collapsed as one unless multiple <br> tags are used.
+func html2Text(htmlDocument string) (string, error) {
+	var builder strings.Builder
+
+	doc, err := html.Parse(strings.NewReader(htmlDocument))
+	if err != nil {
+		return "", err
+	}
+
+	tagsToSkip := []string{
+		"style", "script", "iframe", "applet", "object", "svg", "img",
+		"button", "form", "textarea", "input", "select", "option", "template",
+	}
+
+	inlineTags := []string{
+		"a", "span", "small", "strike", "strong",
+		"sub", "sup", "em", "b", "u", "i",
+	}
+
+	var canAddNewLine bool
+
+	// see https://pkg.go.dev/golang.org/x/net/html#Parse
+	var f func(*html.Node)
+	f = func(n *html.Node) {
+		// start link wrapping for producing "[text](link)" formatted string
+		isLink := n.Type == html.ElementNode && n.Data == "a"
+		if isLink {
+			builder.WriteString("[")
+		}
+
+		switch n.Type {
+		case html.TextNode:
+			txt := whitespaceRegex.ReplaceAllString(n.Data, " ")
+
+			// the prev node has new line so it is safe to trim the indentation
+			if !canAddNewLine {
+				txt = strings.TrimLeft(txt, " ")
+			}
+
+			if txt != "" {
+				builder.WriteString(txt)
+				canAddNewLine = true
+			}
+		case html.ElementNode:
+			if n.Data == "br" {
+				// always write new lines when <br> tag is used
+				builder.WriteString("\r\n")
+				canAddNewLine = false
+			} else if canAddNewLine && !list.ExistInSlice(n.Data, inlineTags) {
+				builder.WriteString("\r\n")
+				canAddNewLine = false
+			}
+
+			// prefix list items with dash
+			if n.Data == "li" {
+				builder.WriteString("- ")
+			}
+		}
+
+		for c := n.FirstChild; c != nil; c = c.NextSibling {
+			if c.Type != html.ElementNode || !list.ExistInSlice(c.Data, tagsToSkip) {
+				f(c)
+			}
+		}
+
+		// end link wrapping
+		if isLink {
+			builder.WriteString("]")
+			for _, a := range n.Attr {
+				if a.Key == "href" {
+					if a.Val != "" {
+						builder.WriteString("(")
+						builder.WriteString(a.Val)
+						builder.WriteString(")")
+					}
+					break
+				}
+			}
+		}
+	}
+
+	f(doc)
+
+	return strings.TrimSpace(builder.String()), nil
+}
diff --git a/tools/mailer/html2text_test.go b/tools/mailer/html2text_test.go
@@ -0,0 +1,131 @@
+package mailer
+
+import (
+	"testing"
+)
+
+func TestHtml2Text(t *testing.T) {
+	scenarios := []struct {
+		html     string
+		expected string
+	}{
+		{
+			"",
+			"",
+		},
+		{
+			"ab  c",
+			"ab c",
+		},
+		{
+			"<!-- test html comment -->",
+			"",
+		},
+		{
+			"<!-- test html comment -->   a   ",
+			"a",
+		},
+		{
+			"<span>a</span>b<span>c</span>",
+			"abc",
+		},
+		{
+			`<a href="a/b/c">test</span>`,
+			"[test](a/b/c)",
+		},
+		{
+			`<a href="">test</span>`,
+			"[test]",
+		},
+		{
+			"<span>a</span>  <span>b</span>",
+			"a b",
+		},
+		{
+			"<span>a</span>   b   <span>c</span>",
+			"a b c",
+		},
+		{
+			"<span>a</span>   b   <div>c</div>",
+			"a b \r\nc",
+		},
+		{
+			`
+				<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+				<html xmlns="http://www.w3.org/1999/xhtml">
+				<head>
+				    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+				    <meta name="viewport" content="width=device-width,initial-scale=1" />
+				    <style>
+				        body {
+				            padding: 0;
+				        }
+				    </style>
+				</head>
+				<body>
+					<!-- test html comment -->
+					<style>
+					    body {
+					        padding: 0;
+					    }
+					</style>
+				    <div class="wrapper">
+				        <div class="content">
+				            <p>Lorem ipsum</p>
+				            <p>Dolor sit amet</p>
+				            <p>
+				            	<a href="a/b/c">Verify</a>
+				            </p>
+				            <br>
+				            <p>
+				            	<a href="a/b/c"><strong>Verify2.1</strong> <strong>Verify2.2</strong></a>
+				            </p>
+				            <br>
+				            <br>
+				            <div>
+				            	<div>
+				            		<div>
+							            <ul>
+							            	<li>ul.test1</li>
+							            	<li>ul.test2</li>
+							            	<li>ul.test3</li>
+							            </ul>
+							            <ol>
+							            	<li>ol.test1</li>
+							            	<li>ol.test2</li>
+							            	<li>ol.test3</li>
+							            </ol>
+				            		</div>
+				            	</div>
+				            </div>
+				            <select>
+				            	<option>Option 1</option>
+				            	<option>Option 2</option>
+				            </select>
+				            <textarea>test</textarea>
+				            <input type="text" value="test" />
+				            <button>test</button>
+				            <p>
+				                Thanks,<br/>
+				                PocketBase team
+				            </p>
+				        </div>
+				    </div>
+				</body>
+				</html>
+			`,
+			"Lorem ipsum \r\nDolor sit amet \r\n[Verify](a/b/c)  \r\n[Verify2.1 Verify2.2](a/b/c)  \r\n\r\n- ul.test1 \r\n- ul.test2 \r\n- ul.test3  \r\n- ol.test1 \r\n- ol.test2 \r\n- ol.test3         \r\nThanks,\r\nPocketBase team",
+		},
+	}
+
+	for i, s := range scenarios {
+		result, err := html2Text(s.html)
+		if err != nil {
+			t.Errorf("(%d) Unexpected error %v", i, err)
+		}
+
+		if result != s.expected {
+			t.Errorf("(%d) Expected \n(%q)\n%v,\n\ngot:\n\n(%q)\n%v", i, s.expected, s.expected, result, result)
+		}
+	}
+}
diff --git a/tools/mailer/smtp.go b/tools/mailer/smtp.go
@@ -68,6 +68,11 @@ func (m *SmtpClient) Send(
 	yak.Subject(subject)
 	yak.HTML().Set(htmlContent)
 
+	// try to generate a plain text version of the HTML
+	if plain, err := html2Text(htmlContent); err == nil {
+		yak.Plain().Set(plain)
+	}
+
 	for name, data := range attachments {
 		yak.Attach(name, data)
 	}

diff --git a/ui/.env b/ui/.env
@@ -4,4 +4,4 @@ PB_PROFILE_COLLECTION = "profiles"
 PB_INSTALLER_PARAM    = "installer"
 PB_RULES_SYNTAX_DOCS  = "https://pocketbase.io/docs/manage-collections#rules-filters-syntax"
 PB_RELEASES           = "https://github.com/pocketbase/pocketbase/releases"
-PB_VERSION            = "v0.5.1"
+PB_VERSION            = "v0.6.0"
diff --git a/ui/dist/assets/CodeEditor.ee0ff101.js → ui/dist/assets/CodeEditor.f01bd0e9.js b/ui/dist/assets/CodeEditor.ee0ff101.js → ui/dist/assets/CodeEditor.f01bd0e9.js